2025 fleets

US airline fleets: age and seats per plane

The 12 airlines ranked on this site flew 4,948 passenger aircraft in 2025, with an average age of 12.7 years. Breeze Airways has the youngest fleet at 3.9 years and Avelo Airlines the oldest at 16.8. The same Airbus A321neo carries 170 seats at JetBlue and 234 at Frontier Airlines.

A passenger jet taxiing past an airport terminal at sunrise — Illustrative photo, not a specific airline's aircraft.

How old is each airline's fleet?

Average age of passenger aircraft in operation, 2025. Age is the filing year minus the year each airframe was built.

Every airline's fleet, 2025

Airline	Aircraft	Average age	Under 5 years	Aged 20 or more	Seats per aircraft	Oldest aircraft
Breeze Airways	54	3.9	85%	0%	133	Embraer E190, 2006
Frontier Airlines	176	4.6	51%	0%	210	Airbus A320, 2015
Spirit Airlines	129	7.5	28%	0%	195	Airbus A320, 2010
Alaska Airlines	243	9.1	39%	6%	170	Boeing 737-700, 1999
Southwest Airlines	803	10.7	32%	17%	163	Boeing 737-700, 2001
JetBlue	291	11.6	29%	25%	162	Airbus A320, 1999
American Airlines	1,013	13.8	13%	28%	182	Airbus A320, 1997
Allegiant Air	123	13.8	13%	25%	178	Airbus A320, 1997
Delta Air Lines	989	14.3	20%	43%	183	Boeing 757-200, 1990
United Airlines	1,058	15.0	27%	44%	182	Boeing 767-300, 1991
Sun Country Airlines	47	16.0	0%	30%	184	Boeing 737-800, 2001
Avelo Airlines	22	16.8	0%	18%	174	Boeing 737-700, 2003

These are the airlines' own aircraft. The regional airlines that fly for United, Delta, American and Alaska file their own fleets, so a mainline airline's fleet doesn't include the regional jets sold under its name. The regional fleets are in the second table below.

The same plane, different seats

An airline chooses how many seats to fit into each aircraft, and the fuel the plane burns changes little with the seat count. More seats on the same model means each one carries a smaller share of the fuel. The Airbus A321neo has 170 seats at JetBlue and 234 at Frontier Airlines, 38% more on the same model.

Boeing 737-800

The Boeing 737-800 has 154 seats at United Airlines and 189 at Avelo Airlines, 23% more on the same model. 7 airlines fly at least 10 of them.

Average seats per Boeing 737-800, 2025, airlines with 10 or more of them.

Boeing 737 MAX 8

The Boeing 737 MAX 8 has 159 seats at Alaska Airlines and 190 at Allegiant Air, 19% more on the same model. 5 airlines fly at least 10 of them.

Average seats per Boeing 737 MAX 8, 2025, airlines with 10 or more of them.

Airbus A321

The Airbus A321 has 177 seats at JetBlue and 230 at Frontier Airlines, 30% more on the same model. 5 airlines fly at least 10 of them.

Average seats per Airbus A321, 2025, airlines with 10 or more of them.

Airbus A320

The Airbus A320 has 142 seats at United Airlines and 184 at Allegiant Air, 30% more on the same model. 6 airlines fly at least 10 of them.

Average seats per Airbus A320, 2025, airlines with 10 or more of them.

Boeing 737-700

The Boeing 737-700 has 120 seats at Alaska Airlines and 143 at Southwest Airlines, 19% more on the same model. 3 airlines fly at least 10 of them.

Average seats per Boeing 737-700, 2025, airlines with 10 or more of them.

All the seat comparisons

Aircraft	Airline	Aircraft of this model	Average seats	Fewest to most	Average age
Boeing 737-800	United Airlines	141	154.0	154	21.5
	Alaska Airlines	59	157.2	157 to 160	17.1
	Delta Air Lines	77	160.0	160	23.9
	American Airlines	303	172.0	172	15.6
	Southwest Airlines	198	175.0	175	9.8
	Sun Country Airlines	44	183.3	68 to 186	16.4
	Avelo Airlines	14	189.0	189	15.5
Embraer E175	Mesa Airlines	60	74.2	70 to 76	9.7
	SkyWest Airlines	270	75.4	70 to 76	7.0
	Envoy Air	136	76.0	76	6.6
	Republic Airways	187	76.0	76	11.9
Boeing 737 MAX 8	Alaska Airlines	14	159.0	159	0.4
	United Airlines	123	163.7	162 to 175	2.0
	American Airlines	89	172.0	172	3.3
	Southwest Airlines	300	175.0	175	2.7
	Allegiant Air	16	190.0	190	0.3
Airbus A321	JetBlue	63	177.2	159 to 200	9.1
	American Airlines	218	183.5	102 to 190	12.9
	Delta Air Lines	127	191.0	191	6.5
	Spirit Airlines	29	222.0	222	8.4
	Frontier Airlines	21	230.0	230	8.8
Airbus A320	United Airlines	68	142.0	142	25.2
	American Airlines	48	150.0	150	24.3
	Delta Air Lines	46	157.0	157	28.5
	JetBlue	130	161.0	150 to 162	19.8
	Spirit Airlines	60	176.0	176	10.8
	Allegiant Air	79	184.0	177 to 186	14.4
Boeing 737-900 and 900ER	United Airlines	148	173.0	173	13.4
	Delta Air Lines	163	179.2	173 to 180	9.5
	Alaska Airlines	79	181.0	181	9.4
Boeing 737-700	Alaska Airlines	11	120.0	120	25.3
	United Airlines	40	124.0	124	26.3
	Southwest Airlines	305	143.0	143	19.1
Airbus A321neo	JetBlue	39	170.2	138 to 200	3.3
	Delta Air Lines	87	190.8	148 to 194	1.6
	American Airlines	86	194.3	155 to 196	4.3
	United Airlines	51	220.0	220	0.6
	Spirit Airlines	21	229.0	229	0.8
	Frontier Airlines	67	234.4	186 to 240	1.1
Airbus A319	United Airlines	76	120.0	120	23.5
	American Airlines	132	128.0	128	21.3
	Delta Air Lines	57	132.0	132	23.4
	Allegiant Air	28	156.0	156	19.8
Bombardier CRJ-900	Endeavor Air	124	76.0	76	14.4
	SkyWest Airlines	46	76.0	76	15.3
	PSA Airlines	89	90.0	90	9.0
Bombardier CRJ-700	Endeavor Air	19	69.0	69	22.1
	PSA Airlines	60	70.0	70	19.2
	SkyWest Airlines	126	70.0	70	19.7
Airbus A220-300	Delta Air Lines	36	130.0	130	2.2
	Breeze Airways	46	137.0	137	1.4
	JetBlue	59	140.0	140	1.5

Does a younger fleet burn less?

Across the 9 airlines that fly no regional partner and have at least 20 aircraft, younger fleets tend to fly more seat-miles per gallon. Fleet age accounts for about 10% of the differences in seat-miles per gallon between them, which is a weak link. Age is a poor guide on its own. A new aircraft is more efficient than the model it replaced, but an airline that squeezes more seats into an older plane can come out ahead of one that flies a newer, roomier one, and how full the flights are matters as well. The aircraft pages show how the types compare, and the rankings show the result for each airline.

How fleets have aged since 2006

Average age of passenger aircraft, all large airlines together and the five largest fleets, 2006 to 2025.

Across these airlines the average age was 10.7 years in 2006 and 12.7 years in 2025.

Regional airline fleets

The regional airlines, 2025

Regional airline	Aircraft	Average age	Seats per aircraft	Oldest aircraft
Envoy Air	179	9.7	73	Embraer E170, 2004
Mesa Airlines	60	9.7	74	Embraer E175, 2014
PSA Airlines	149	13.1	82	Bombardier CRJ-700, 2001
Republic Airways	249	13.9	74	Embraer E170, 2004
SkyWest Airlines	581	14.0	68	Bombardier CRJ-700, 1999
Endeavor Air	143	15.4	75	Bombardier CRJ-700, 2002
CommuteAir	49	21.0	50	Embraer ERJ-145, 2002
Piedmont Airlines	71	21.8	50	Embraer ERJ-145, 1999
Air Wisconsin Airlines	54	22.8	50	Bombardier CRJ-200, 1998

Where the figures come from. The US Bureau of Transportation Statistics collects an annual inventory of every aircraft each large airline operates (Form 41, Schedule B-43), with the year the airframe was built, the model and the usual number of seats. We count passenger aircraft in operation, which means a status of operating and 10 or more seats, so freighters and parked aircraft are left out. Models are typed by each airline in its own style, so we group them into families by their text. The seat count is the airline's own filed figure and can lag a cabin refit. Fleet size here isn't the same as the flying measured on the methodology page, and the inventory covers 2006 to 2025.

See how the airlines compare on fuel on the airline pages, or the fuel burn of each type on the aircraft pages.